Tractor.



A J. TRIGWELL.

TRACTOR.

APPLICATION FILED SEPT. 5, 1916.

Patented May 28, 1918.

W NT R ALFRED J. TRIGWELL, OF SAN JOSE, CALIFORNIA.

TRACTOR.

Specification of Letters Patent.

Patented May 2d, 191%..

Application filed September 5, 1916. Serial No. 118,380.

To all whom it may concern:

Be it known that I, ALFRED J. TRIGWELL, a subject of the King of Great Britain, and a resident of San Jose, in the county of Santa Clara and State of California, have invented certain new and useful Improvements in Tractors, of which the following is a specification.

My invention relates to tractors, and particularly to that portion of the driving mechanism comprising the track and the sproclc cts upon which said track is mounted.

It is the object of my invention to provide a track in which the numerous runall parts may be eliminated. ln'those forms. of track now commonly used the numerous plates or shoes are connected in such a man nor as to otier a multitude of wearing surfaces with their attendant dil'liculties and to provide a great number of parts of various shapes and sizes that not only add greatly to the first cost of the track but also renders the track constantly subject to repair. It is, therefore, the object of my invention to so simplify the construction of of the track that any broken part may be quickly and easily replaced with a new part. and that the wearing surfaces above referred to may be practically eliminated and consequently provide a track that may be properly called frictionless.

With the above and other objects in view, the invention consists in the novel and useful provision, formation, construction, combination and relative arrangement of parts as hereinafter described and shown in the accompanying drawing, in which,

Figure 1 is a side elevation of a portion of a tractor showing my improved track in position, parts being broken away.

Fig. 9. is an enlarged section on line AA of Fig. 1.

Fig. 3 is an enlarged section on line B-B of Fig. 1.

Fig. 4; is a plan view of the inner surface of the track, part being broken away.

Fig. 5 is a sectional View through a coun tor-sunk plate or shoe.

Similar characters of reference refer to similar parts throughout the several views.

Referring now more particularly to the drawings 1 indicates a portion of a tractor frame upon which are mounted sprockets 2 and 3. Sprockets 2 and 3 are provided with a number, in this case 8, of transverse grooves 4: equally spaced about the outer circumference thereof, and are also provided with three annular parallel channyls 5 formed in their outer or wearing sur fti'ces. The track proper, which forms the principal subject matter of this invention, consists three cables (3 carrying a plurality of sh es 7 secured thereto by bars 8 and bolts 9. \Vhen the track is assembled as shown in part in Fig. 4, the shoes 7 are secured to cables 6 so that their longer edges are adjacent to each other, and said cables (3 are so arranged that the ends of each cable approach each other between different shoes from any other cable as indicated at 10, 11 and 12 respectively. The track being new placed on sprockets 2 and 3 and given the proper tension by adjustment 13, it is ready for use. Frame 14- and idlers 15 as well as adjustment 18, may be provided substantially the same as those now in common use. ldlers 15 should, however, carry a belt 16 to engage bars 8 and thereby provide a smooth running surface for the same. In attaching cables 6 to shoes 7 it is desirable to drill shoes 7 as indicated at 17 and to tap bars 8 as indicated at. 18, then boltstt) may be screwed into bars 8 thereby drawing the same up tightly against shoes 7 and securely gripping cables 6. Inasmuch as bolts 9 may project a distance through bars 8, and also since sand or other foreign matter may tend to collect in grooves 1, it is desirable to provide a number of openings, as 19, in each of said sprockets to receive said projecting bolts and to permit the expulsion of said foreign matter theretlnrough when bars 8 enter said grooves 4.

11; is understood, of course. that While 1 have shown and described in detail one par ticular method of constriu-tion 1 do not wish to confine myself to the mrticular construe tien shown and described as various forms of shoes may be used, such as shown in Fig. 5 in which the outer face is (punter-sunk to receive the bolt head, and various methods may be used for securing the shoes to the cables. Also while I have shown and described cables for connecting shoes 7, a chain or other continuous element may be used depending upon the exigencies of manufacture. The number of channels in each sprocket would of course correspond with the number of connecting elements used.

Having thus described my invention vWhat I claim asnew and desire to secure by Letters Patent, is;

1. In a tractor, a pair of sprockets, each sprocket having a plurality of transversely positioned grooves and a plurality of annular channels formed in the outer circumference thereof, and an endless track adapted to be carried by said sprockets, said truck comprising a plurality of flexible connecting elements adapted to engage said channels, and a plurality of juxtaposed shoes secured to said connecting elements, each shoe having a bar secured to its inner surface adapted to engage one of said transverse grooves.

2. In a tractor, a pair of sprockets, each sprocket having a plurality of transversely positioned grooves and a plurality of annular channels formed in the outer circumference thereof, and an endless track adapted to be carried by said sprockets, said track comprising a plurality of flexible connecting elements adapted to engage said channels, and a plurality of juxtaposed shoes secured to saidconnecting elements, each shoe'hav- ,ing a bar secured to its inner surface adapted to engage one of said transverse grooves, and. each of said grooves having open communication with the inner circumference of the sprocket in which it is formed.

3. A traction belt composed of a plurality of independent juxtaposed shoes having substantially fiat inner surfaces, a plurality of cables along which said shoes are arranged, and a plurality of bars, each bar having a fiat side for engagement with the flat inner surface of said shoes, and a plurality of transverse grooves formed in said flat side for spacing and engaging said cables, and means for detachably securing one of said bars to the inner surface of each shoe.

4. In a tractor, a pair of sprockets, each sprocket having a plurality of transversely positioned grooves and a plurality of annular channels formed in the outer circumference thereof, and an endless track adapted to be carried by said sprockets, said track comprising a plurality of flexible connecting elements adapted to engage said channels, and a plurality of juxtaposed shoes secured to said connecting elements by means of a bar secured to the inner surface of each shoe and adapted to tightly engage said connecting elements, said bars being adapted to engage said transverse grooves in said sprockets, and each of said connecting elements having its ends approach each other between a different pair of shoes from any other connecting element.

5. In a tractor, a pair of sprockets, each sprocket having a plurality of transversely positioned grooves and a plurality of annular channels formed in the outer circumference thereof, and an endless track adapted to be carried by said sprockets, said track comprising a plurality of flexible connecting elements adapted to engage said channels, and a pluralitybf juxtaposed shoes secured to said connecting elements by means of a transversely grooved bar secured to each of said shoes and adapted to tightly engage said connecting elements said bars being adapted to engage said transverse grooves in said sprockets.

In testimony whereof I have hereunto aflixed my signature this 29th day of August, 1916.

ALFRED J. TRIGWVELL. 

